1. AKARI far-infrared maps of the zodiacal dust bands
- Author
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Ootsubo, Takafumi, Doi, Yasuo, Takita, Satoshi, Nakagawa, Takao, Kawada, Mitsunobu, Kitamura, Yoshimi, Matsuura, Shuji, Usui, Fumihiko, and Arimatsu, Ko
- Subjects
Astrophysics - Earth and Planetary Astrophysics - Abstract
Zodiacal emission is thermal emission from interplanetary dust. Its contribution to the sky brightness is non-negligible in the region near the ecliptic plane, even in the far-infrared (far-IR) wavelength regime. We analyse zodiacal emission observed by the AKARI far-IR all-sky survey, which covers 97% of the entire sky at arcminute-scale resolution in four photometric bands, with central wavelengths of 65, 90, 140, and 160 $\mu$m. AKARI detected small-scale structures in the zodiacal dust cloud, including the asteroidal dust bands and the circumsolar ring, at far-IR wavelengths. Although the smooth component of the zodiacal emission structure in the far-IR sky can be reproduced well by models based on existing far-IR observations, previous zodiacal emission models have discrepancies in the small-scale structures compared with observations. We investigate the geometry of the small-scale dust-band structures in the AKARI far-IR all-sky maps and construct template maps of the asteroidal dust bands and the circumsolar ring components based on the AKARI far-IR maps. In the maps, $\pm 1.4\deg$, $\pm 2.1\deg$ and $\pm 10\deg$ asteroidal dust-band structures are detected in the 65 $\mu$m and 90 $\mu$m bands. A possible $\pm 17\deg$ band may also have been detected. No evident dust-band structures are identified in either the 140 $\mu$m or the 160 $\mu$m bands. By subtracting the dust-band templates constructed in this paper, we can achieve a similar level of flux calibration of the AKARI far-IR all-sky maps in the $|\beta| < 40\deg$ region to that in the region for $|\beta| > 40\deg$., Comment: 27 pages, 10 figures, and 3 tables, accepted for publication in PASJ
- Published
- 2016
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